LinuxQuestions.org - [SOLVED] sort command help

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sort command help

In a file there are two entries -->
Windows NT
Windows2008

In AIX ==>
sort filename >
Windows NT
Windows2008

In Linux the same command with the same file produces
Windows2008
Windows NT

Could anyone please explain...is this because the space is treated differently in AIX & LINUX during sort...

Thanks for help

Hi,

Sort uses the locale specified in the environment (the LC_ALL=xxx setting), that is probably why there is a difference in the output.

Although not all sort version support it, try using AIX sort's -A option. You could also set LC_ALL to c (LC_ALL=C), but the latter may influence more then just sort!! Be careful if this is a production environment.

Hope this clears things up a bit.

I don't know about windows, but the sorting order in unix depends on the locale. Unicode sort order especially is different from the C/POSIX order. If you set your LC_COLLATE environment variable to either C or POSIX, the sorting of the above becomes the same.

Edit: Aargh, beaten by Druuna. But I can at least point out that setting LC_COLLATE only is more specific than setting LC_ALL, and won't affect the whole system.

Not sure on the answer because on my system, a space is sorted ahead of a "2" while "Windows2008" is sorted before "Windows NT".
I tried using -t' ' to change the field separator, without any difference. The order was always this way.

I took a peek at sort.c:

Code:

#ifdef POSIX_UNSPECIFIED

  /* The following block of code makes GNU sort incompatible with

    standard Unix sort, so it's ifdef'd out for now.

    The POSIX spec isn't clear on how to interpret this.

    FIXME: request clarification.



    From: kwzh@gnu.ai.mit.edu (Karl Heuer)

    Date: Thu, 30 May 96 12:20:41 -0400

    [Translated to POSIX 1003.1-2001 terminology by Paul Eggert.]



    [...]I believe I've found another bug in `sort'.



    $ cat /tmp/sort.in

    a b c 2 d

    pq rs 1 t

    $ textutils-1.15/src/sort -k1.7,1.7 </tmp/sort.in

    a b c 2 d

    pq rs 1 t

    $ /bin/sort -k1.7,1.7 </tmp/sort.in

    pq rs 1 t

    a b c 2 d



    Unix sort produced the answer I expected: sort on the single character

    in column 7.  GNU sort produced different results, because it disagrees

    on the interpretation of the key-end spec "M.N".  Unix sort reads this

    as "skip M-1 fields, then N-1 characters"; but GNU sort wants it to mean

    "skip M-1 fields, then either N-1 characters or the rest of the current

    field, whichever comes first".  This extra clause applies only to

    key-ends, not key-starts.

    */



  /* Make LIM point to the end of (one byte past) the current field.  */

  if (tab != NULL)

    {

      char *newlim;

      newlim = memchr (ptr, tab, lim - ptr);

      if (newlim)

        lim = newlim;

    }

  else

    {

      char *newlim;

      newlim = ptr;

      while (newlim < lim && blanks[to_uchar (*newlim)])

        ++newlim;

      while (newlim < lim && !blanks[to_uchar (*newlim)])

        ++newlim;

      lim = newlim;

    }

#endif

Actually, on this case, the original GNU interpretation is what I expected. A decimal point implies what follows is part of a field and not potentially several fields.

Thank you all for the explanations..